The present invention relates to a test reagent for detecting fibrin monomers and a method of detecting the same in human blood plasma.
The appearance of fibrin monomers in blood is a proof of an activation of the hemostasis system. This is a clinically frequently occurring symptom of many basic illnesses. Therefore, after the hypercoagulation stage, locally caused thromboses or generally coagulation pathologies can develop with resulting heavy bleeding. The possible early detection of coagulating activity is a prerequisite for an effective therapy.
Several principles for detecting the fibrin monomers are known in the art. The oldest methods include the ethanol-gelatin test in accordance with GODAL (H. GODAL and U. ABILGAARD, Scand. J. Haem. 3, 1966, 342) and the protamine sulfate test in accordance with LIPPINSKI (B. LIPPINSKI and K. WAROWSKI, Thromb. Diath. Haem. 20, 1968, 44). These methods are easy to carry out. However, they show an insufficient sensitivity and specificity. A specific test is the agglutination test with fibrin monomer loaded erythrocytes in accordance with LARGO (R. LARGO et al., Blood 47, 1976, 991). Furthermore, the test suitable for the diagnosing of von Willebrand's disease based on the precipitator Ristocetin-A (Ristomycin-A) is used for detecting of fibrin monomers (K. WATANABE and J. L. TULLIS, Amer. J. Clin. Pathol. 70, 1978, 691; G. PFLIEGLER et al. Abstr. Int. Congr. ISH-ISBT, Budapest, Aug. 1982, p. 380). Numerous comparative tests have shown that with the above listed precipitators, an nonspecific precipitation with fibrin cleavage products takes place, and with increasing thrombocyte content of the plasma used for detection, falsely positive reactions are obtained so that the reliability of the test is not guaranteed. In addition to the above methods, also various further methods which are connected with expensive analysis techniques are known (affinity chromatography gel-filtration).